CN108818366B

CN108818366B - Bushing positioning and clamping mechanism

Info

Publication number: CN108818366B
Application number: CN201810626756.5A
Authority: CN
Inventors: 李志栋; 樊晓娟; 徐天航; 纪欢欢; 吴红军; 秦楚山
Original assignee: AVIC Landing Gear Advanced Manufacturing Corp
Current assignee: AVIC Landing Gear Advanced Manufacturing Corp
Priority date: 2018-06-19
Filing date: 2018-06-19
Publication date: 2020-04-10
Anticipated expiration: 2038-06-19
Also published as: CN108818366A

Abstract

The invention discloses a bushing positioning and clamping mechanism which comprises a sleeve component and a clamping device, wherein the clamping device comprises a seat body, a clamping jaw, a driving device and a guide shaft, wherein the guide shaft is fixed on the seat body along the central axis X of the seat body, and the lower end of the guide shaft extends out of the bottom surface of the seat body; the sleeve assembly comprises a mandrel, a clamping part and a limiting device, wherein the mandrel can be in clearance fit with the lining, the clamping part is fixedly arranged at the top of the mandrel and can be clamped by a clamping jaw, the limiting device is arranged at the bottom of the mandrel and can support the lining, a central hole is formed in the clamping part, and the mandrel and the clamping part have the same central axis Y; the top surface of the clamping part can be tightly attached to the bottom surface of the seat body, and the attaching surface is vertical to the central axis Y; during fitting, the guide shaft is inserted into the central hole, the guide shaft is in small clearance fit with the central hole, and the axis of the guide shaft is collinear with the central axis Y. The invention selects holes and surface positioning to limit the degree of freedom, and has simple, accurate and reliable installation positioning, high installation efficiency and high installation quality.

Description

Bushing positioning and clamping mechanism

Technical Field

The invention belongs to an automatic high-precision positioning technology of a bushing, and particularly relates to a bushing positioning and clamping mechanism which is particularly suitable for large-size bushings.

Background

The bush often can be used in the assembly of axle type part, and traditional bush mounting means often adopts the mode of artifical striking, directly impresses the bush in the shaft hole by force, and this kind of mode is not to the assembly that the required precision is not high can, but to the high condition of assembly precision and positioning accuracy requirement, traditional mode can not satisfy the requirement, causes the destruction to shaft hole or bush easily moreover.

For the field of aircraft manufacturing, bushings with large size and specifications and lengths of more than 500mm are often encountered, the requirements on precision and automatic installation are high, the requirement on positioning of the installed bushing in the correct posture is very high, a reasonable and reliable positioning reference is needed, and the degree of freedom is effectively limited. At present, the assembly capability of large-size thin-wall bushings is not available at home, and because the assembly of the bushings is a step in the production process of products, foreign aircraft manufacturers usually adopt a secret technology mode to protect the assembly process, and products imported to home can only see the assembled bushings and cannot restore the assembly process.

In view of the above, with the advance of "2025 made in china", the machining and assembling process gradually develops toward automation and intellectualization, and there is a great need in China to develop automation equipment to realize high-precision automatic and rapid positioning of bushing assembly and improve efficiency and quality.

Disclosure of Invention

Aiming at the problems, the invention aims to provide a bushing positioning and clamping mechanism before the bushing is installed, so that the problems of long manual operation time, inaccurate positioning and unsafe press-fitting process are solved, and automatic and reliable clamping and positioning in determined time are realized.

The technical scheme for solving the problems is as follows: a bushing positioning and clamping mechanism comprises a sleeve component and a clamping device, wherein the clamping device comprises a base body, clamping jaws, a driving device and a guide shaft, the driving device is fixed on the base body and can drive the clamping jaws to synchronously open and clamp, the guide shaft is fixed on the base body along the central axis X of the base body, and the lower ends of the guide shaft extend out of the bottom surface of the base body;

the sleeve assembly comprises a mandrel, a clamping part and a limiting device, wherein the mandrel can be in clearance fit with the lining, the clamping part is fixedly arranged at the top of the mandrel and can be clamped by a clamping jaw, the limiting device is arranged at the bottom of the mandrel and can support the lining, a central hole is formed in the clamping part, and the mandrel and the clamping part have the same central axis Y;

the top surface of the clamping part can be tightly attached to the bottom surface of the seat body, and the attaching surface is vertical to the central axis Y; during fitting, the guide shaft is inserted into the central hole, the guide shaft is in small clearance fit with the central hole, and the axis of the guide shaft is collinear with the central axis Y.

When the bushing is sleeved on the outer surface of the mandrel, the clamping part can be clamped through the clamping device, one surface of the base body and the top surface of the clamping part, and the guide shaft and the central hole are positioned in the clamping process, so that the positioning is simple, accurate and reliable.

Specifically, the clamping part comprises a cylindrical body, a flange with the diameter larger than that of the body is arranged at the top of the body, and the top surface of the flange can be tightly attached to the bottom surface of the seat body;

the bottom of the body is connected with the top of the mandrel.

The lower end of the clamping jaw is provided with a horizontal part which can be simultaneously abutted against the edge of the bottom surface of the flange and the outer surface of the body, so that the clamping part can be clamped.

Specifically, the base body comprises a cylindrical base body with a hollow cavity and a flange detachably connected with the lower end of the base body, the lower end of the guide shaft penetrates out of the center of the flange, the guide shaft is in transition fit with the flange, and the bottom surface of the flange is the bottom surface of the base body.

The flange has two functions: firstly, the center of the guide shaft can be used for fixedly guiding the guide shaft; the bottom surface of the second flange is used as a reference surface to be attached to the top surface of the clamping part for positioning.

Furthermore, the top of the guide shaft is connected with a second cylinder, the second cylinder is fixed in the hollow cavity of the seat body, and the guide shaft can move along the central axis X of the seat body.

Furthermore, the driving device comprises a connecting rod and a first air cylinder fixed on the seat body, and a piston rod of the first air cylinder is hinged with the upper end of the clamping jaw; one end of the connecting rod is hinged with the base body, and the other end of the connecting rod is hinged with the clamping jaw;

the jaws are opened and closed in the reciprocating motion of the piston rod.

Preferably, the number of the clamping jaws is three, and each clamping jaw is correspondingly provided with one set of driving device.

Preferably, the lower end of the guide shaft is a conical surface. The shape of the conical surface can guide accurate positioning.

Further, the mandrel is a hollow shaft;

the limiting device comprises a bottom cover detachably connected with the lower end of the mandrel, a plurality of screw holes are formed in the side wall of the bottom cover along the circumferential direction and perpendicular to the central axis Y, a ball plunger screw is arranged in each screw hole, the diameter of a ball head of each ball plunger screw is larger than the diameter of the hole of the screw hole close to one end of the outer wall of the mandrel, and each ball head is tightly jacked and correspondingly clamped in the hole of one screw hole.

The ball plunger screw is a standard part, the ball is tightly propped at the orifice by the spring, and force is applied to the ball from outside to inside, so that the ball can be retracted.

The invention has the following remarkable effects:

1. the freedom degree is limited by selecting holes and surface positioning, positioning is carried out by utilizing the mode that the guide shaft is attached to the central hole and the end face, the mounting and positioning are simple, accurate and reliable, and the mounting efficiency and the mounting quality are high.

2. A set of grasping device with a fixed rotating fulcrum is designed, a power source is provided by using an air cylinder, tensioning and loosening are realized, the principle is simple, and the operation is convenient.

3. Can be popularized to the precise positioning assembly under various angles in space, and has strong popularization and reference significance.

Drawings

The invention will be further explained with reference to the drawings.

FIG. 1 is a front view of a sleeve assembly.

FIG. 2 is a top view of the sleeve assembly.

FIG. 3 is a diagram of a grip device configuration.

Fig. 4 is a schematic view of the working state of the positioning and clamping mechanism.

Fig. 5 is a view a-a of fig. 4.

Fig. 6 is an enlarged view of i in fig. 5.

Fig. 7 is a schematic view of a ball plunger screw structure.

Fig. 8 is a thin-walled bushing block diagram.

In the figure: 1-sleeve component, 2-gripping device, 3-clamping part, 4-limiting device, 5-bushing, 8-second cylinder, 9-first cylinder, 10-connecting rod, 11-mandrel, 21-seat, 22-claw, 23-guide shaft, 31-central hole, 32-body, 33-flange, 41-bottom cover, 42-screw hole, 43-ball plunger screw, 44-ball head, 220-horizontal part, 211-base body and 212-flange.

Detailed Description

As shown in FIGS. 1 to 8, a bushing positioning and clamping mechanism comprises a sleeve component 1 and a grasping device 2.

The grasping device 2 includes a base 21, a plurality of jaws 22, a driving device fixed on the base 21 and capable of driving the jaws 22 to open and clamp synchronously, and a guide shaft 23 disposed on the base 21 along a central axis X of the base 21.

The base body 21 comprises a cylindrical base body 211 with a hollow cavity and a flange 212 detachably connected with the lower end of the base body 21. The lower end of the guide shaft 23 penetrates out of the center of the flange 212. The guide shaft 23 is in transition fit with the flange 212, and the bottom surface of the flange 212 is the bottom surface of the seat body 21.

The top of the guide shaft 23 is connected with a second cylinder 8. The second cylinder 8 is fixed in the hollow cavity of the seat body 21. The guide shaft 23 is movable along the central axis X of the seat body 21. The lower end of the guide shaft 23 is a conical surface.

The driving device comprises a connecting rod 10 and a first air cylinder 9 fixed on a seat body 21. The piston rod of the first cylinder 9 is hinged with the upper end of the claw 22. One end of the connecting rod 10 is hinged with the seat body 21, and the other end is hinged with the claw 22. The number of the clamping jaws 22 is three, and each clamping jaw 22 is correspondingly provided with a set of driving device. Jaws 22 effect expansion and contraction during reciprocation of the piston rod.

The sleeve component 1 comprises a hollow mandrel 11 which can be in clearance fit with the bush, a clamping part 3 which is fixedly arranged at the top of the mandrel 11 and can be clamped by a clamping claw 22, and a limiting device 4 which is arranged at the bottom of the mandrel 11 and can support the bush. The mandrel 11 is used for installing, supporting and fixing the thin-wall bushing.

The gripping part 3 includes a cylindrical body 32. The bottom of the body 32 is connected to the top of the mandrel 11. A flange 33 having a diameter larger than that of the body 32 is provided on the top of the body 32. The gripping part 3 is provided with a center hole 31. The mandrel 11 has the same central axis Y as the gripping part 3.

The top surface of the flange 33 can be tightly attached to the bottom surface of the seat body 21, and the attachment surface is perpendicular to the central axis Y. During fitting, the guide shaft 23 is inserted into the central hole 31, the guide shaft 23 is in small clearance fit with the central hole 31, and the axis of the guide shaft 23 is collinear with the central axis Y.

The lower end of the claw 22 is provided with a horizontal part 220, and the horizontal part 220 can be simultaneously abutted with the edge of the bottom surface of the flange 33 and the outer surface of the body 32, so as to clamp the clamping part 3.

The limiting device 4 comprises a bottom cover 41 detachably connected with the lower end of the mandrel 11. A plurality of screw holes 42 are formed in the side wall of the bottom cover 41 along the circumferential direction and perpendicular to the central axis Y. A ball plunger screw 43 is provided in each screw hole 42. The diameter of the ball 44 of the ball plunger screw 43 is larger than the diameter of the hole of the screw hole 42 near one end of the outer wall of the mandrel 11. Each ball head 44 is tightly pressed and correspondingly clamped at the opening of one screw hole 42.

When the device works, the thin-wall bushing 5 is sleeved on the outer circular surface of the mandrel 11 through the inner wall extrusion bulb 44. The first air cylinder 9 is started to work, the first air cylinder 9 performs telescopic motion under the control of an NC program, a piston rod is retracted upwards, the three clamping jaws 22 are drawn by the piston rod and drawn by the connecting rod 10 to contract upwards and inwards, the bottom surface of the clamping flange 33 and the outer circular surface of the body 32 contract inwards, the mandrel 11 is lifted upwards, the guide shaft 23 is inserted into the central hole 31, so that the sleeve assembly moves upwards along the direction of the guide shaft 31, the top surface of the flange 33 is attached to the bottom surface of the flange 212, and the positioning accuracy and precision are ensured.

The thin-wall bushing 5 and the shell can be assembled in a mode of thermal expansion and cold contraction subsequently, after the thin-wall bushing 5 is installed in place, the guide shaft 23 retracts from the central hole 31 under the action of the second air cylinder 8, the clamping jaws 22 are loosened, the sleeve component 1 is left, and after the thin-wall bushing 5 is subjected to cold and hot deformation to reach balance and interference, the sleeve component 1 is pulled out manually. The purpose of the movable guide shaft 23 is to facilitate the subsequent steps and to avoid the displacement of the sleeve assembly 1 caused by the guide shaft 23 being pulled out of the central hole 31 without the jaws 22 gripping.

Claims

1. The utility model provides a bush location clamping machine constructs which characterized in that: the clamping device comprises a sleeve component (1) and a clamping device (2), wherein the clamping device (2) comprises a base body (21), a jaw (22), a driving device which is fixed on the base body (21) and can drive the jaw (22) to synchronously open and clamp, and a guide shaft (23) which is arranged on the base body (21) along the central axis X of the base body (21), and the lower end of the guide shaft (23) extends out of the bottom surface of the base body (21);

the sleeve component (1) comprises a mandrel (11) which can be in clearance fit with the bushing, a clamping part (3) which is fixedly arranged at the top of the mandrel (11) and can be clamped by a clamping jaw (22), and a limiting device (4) which is arranged at the bottom of the mandrel (11) and can support the bushing, wherein a central hole (31) is formed in the clamping part (3), and the mandrel (11) and the clamping part (3) have the same central axis Y;

the top surface of the clamping part (3) can be tightly attached to the bottom surface of the base body (21), and the attachment surface is vertical to the central axis Y; when in attaching, the guide shaft (23) is inserted into the central hole (31), the guide shaft (23) is in small clearance fit with the central hole (31), and the axis of the guide shaft (23) is collinear with the central axis Y.

2. The bushing positioning and clamping mechanism according to claim 1, wherein: the clamping part (3) comprises a cylindrical body (32), the top of the body (32) is provided with a flange (33) with the diameter larger than that of the body (32), and the top surface of the flange (33) can be tightly attached to the bottom surface of the seat body (21);

the bottom of the body (32) is connected with the top of the mandrel (11).

3. The bushing positioning and clamping mechanism according to claim 2, wherein: the lower end of the clamping jaw (22) is provided with a horizontal part (220), and the horizontal part (220) can be simultaneously abutted against the edge of the bottom surface of the flange (33) and the outer surface of the body (32) so as to clamp the clamping part (3).

4. A bush positioning and clamping mechanism as claimed in claim 1 or claim 2, wherein: the base body (21) comprises a cylindrical base body (211) with a hollow cavity and a flange (212) detachably connected with the lower end of the base body (211), the lower end of the guide shaft (23) penetrates out of the center of the flange (212), the guide shaft (23) is in transition fit with the flange (212), and the bottom surface of the flange (212) is the bottom surface of the base body (21).

5. The bushing positioning and clamping mechanism according to claim 4, wherein: the top of the guide shaft (23) is connected with a second cylinder (8), the second cylinder (8) is fixed in the hollow cavity of the seat body (21), and the guide shaft (23) can move along the central axis X of the seat body (21).

6. A bush positioning and clamping mechanism as claimed in claim 1 or claim 2, wherein: the driving device comprises a connecting rod (10) and a first air cylinder (9) fixed on the seat body (21), and a piston rod of the first air cylinder (9) is hinged with the upper end of the clamping jaw (22); one end of the connecting rod (10) is hinged with the seat body (21), and the other end of the connecting rod is hinged with the clamping jaw (22);

the jaws (22) are expanded and contracted during the reciprocating motion of the piston rod.

7. The bushing positioning and clamping mechanism according to claim 6, wherein: the number of the clamping jaws (22) is three, and each clamping jaw (22) is correspondingly provided with one set of driving device.

8. The bushing positioning and clamping mechanism according to claim 1, wherein: the lower end of the guide shaft (23) is a conical surface.

9. A bush positioning and clamping mechanism as claimed in claim 1 or claim 2, wherein: the mandrel (11) is a hollow shaft;

stop device (4) include bottom (41) of being connected with dabber (11) lower extreme can be dismantled, have seted up a plurality of screws (42) along circumference and perpendicular to the central axis Y on bottom (41) lateral wall, be equipped with bulb plunger screw (43) in every screw (42), bulb (44) diameter of bulb plunger screw (43) is greater than the aperture that is close to screw (42) the hole department of the one end of dabber (11) outer wall, each bulb (44) all by the top tight and correspond the card and fix in a screw (42) hole department.